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The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

The thermal management system for electric vehicles is developed. Called the Thermal Link System, it consists of a heat-pump air conditioner, a system recovering waste heat from the electric power train, and a heat exchanger between the air-conditioner refrigerant and the power-train coolant water. The recovered heat is used for interior heating, so the amount of power consumed by the heat-pump air conditioner can be reduced. In this system the refrigerant for the heat-pump air conditioner and the coolant water for electric power trains are thermally linked by the heat exchanger, which can reduce the temperature of the coolant water to less than that of the surrounding air. This enhanced cooling function increases the power of electric power trains, or extends the amount of time at full power operation. Here we describe the Thermal Link System's mechanism and effects on energy efficiency.

This paper describes Virtual-Hardware-In-the-Loop Simulation (VHILS), a new validation method for real-time control systems. HILS integrates multiple-technology domain simulators and uses no actual hardware components. Target software in binary code formats are executed with CoMET™, a virtual processor platform and physical layer signals are emulated with MATLAB®/Simulink®. Thus, VHILS can replace HILS, which is widely used for control software validation today. The VHILS was applied to the development of adaptive cruise control system (ACCS), and driver maneuvering, vehicle dynamics, microcontroller operation and CAN communication were modeled. The data exchange between multi-domain simulation and communication modeling were identified to be the primary causes of longer computational time.

This paper proposes and evaluates improvements to a crash simulation of a fuel delivery module in a fuel tank. The simulations were performed in ANSYS/LS-DYNA. Deviations between the original simulation and test data were studied and reasons for the deviations hypothesized. These reasons stemmed from some of the simplifying assumptions of the model. Improvements consisted of incorporating plasticity and strain rate effects into the material models. Performance criteria were also directly incorporated into the material models such that non-performing portions of the model could be deactivated during the simulation. Finally, solid-fluid interactions were added into the simulation to include the momentum transfer from fuel to the fuel delivery module. It was previously thought that effects of a crash would be most severe on the module when the fuel tank was empty and the module was full with fuel.

Networking of active and passive safety is the fundamental basis for comprehensive vehicle safety. Situation-relevant information relating to driver reactions, vehicle behavior and traffic environment are fed into a crash probability calculator, which continually assesses the current crash risk and intervenes when necessary with appropriate measures to avoid a crash and reduce potential injuries. This provides effective protection not only for vehicle occupants but also for other, vulnerable road users. As this functionality up till now only relates to the vehicle itself, the next logical step is enhancement leading to the ultimate goal in safety performance, telematics. The integration of this embedded, in-vehicle wireless communication system allows Car-to-Car (C2C) and Car-to-Infrastructure (C2I) functionality for, e.g. hazard warning. This is an integral element of the cascaded ContiGuard® protection measures.

The AUTomotive Open System ARchitecture (AUTOSAR) Development Partnership has published early 2008 the specifications Release 3.0 [1], with a prime focus on the overall architecture, basic software, run time environment, communication stacks and methodology. Heavy developments have taken place in the OEM and supplier community to deliver AUTOSAR loaded cars on the streets starting 2008 [2]. The 2008 achievements have been: Improving the specifications in order to secure the exploitation for body, chassis and powertrain applications Adding major features: safety related functionalities, OBD II and Telematics application interfaces.

Bio-ethanol can be produced from several type of biomass, and the CO2 emission of bio-ethanol is low compared with gasoline. Bio-ethanol is a high octane fuel, therefore, it has characteristics that allow it to burn at a high compression ratio condition. However, bio-ethanol is usually refined to be high purity ethanol (>99.5%). It requires much energy to refine; thus large-scale refinery plants are needed, increasing the cost of refining bio-ethanol. High purity ethanol (>99.5%) can be refined after fermentation and a distillation. If hydrous ethanol can be used as a fuel for engines, the distillation process can be simplified. As a result, the costs of refinement can be reduced. An innovated engine can be developed by using hydrous ethanol as the fuel because three highly efficient methods can be combined. First, exhaust heat can be recovered by the steam reforming of hydrous ethanol. Second, the reformed gas, which contains hydrogen, can be combusted under dilute conditions.

We developed a novel method for reducing the engine noise associated with the high-pressure fuel system in gasoline direct-injection (DI) engines. We focused on the level of noise at idle running speed, because at the idle state, engine noise is the only noise source to the driver. The dominant vibration source of the high-pressure fuel system was fuel pulsation from the high-pressure fuel pump and activation noise of the solenoid-drive injector. To reduce the noise of the idling engine, we focused on the vibration transmission path from the high-pressure fuel system to the cylinder head, which results in noise radiation from the engine block. Next, we focused on the radiation noise associated with the pressurization event of the high-pressure fuel pump. To reduce the vibration transmission from the high-pressure fuel system to the cylinder head, the fuel rail and the injector were isolated from the cylinder head by avoiding metal-to-metal contact.

In the research project between the Institute of Automotive Engineering (FZD) of the Technische Universität Darmstadt (TUD) and Continental Teves AG & Co. oHG a new modeling concept has been developed. With the aim to enhance the current development process, the brake caliper is modeled based on coupled rigid bodies integrated into a nonlinear system model. Using an explicit interface definition, the number of degrees of freedom is minimized and the calculation of caliper performance is possible over a wide range of parameters. Compared to models based on the Finite Element Method (FEM), fully parameterized geometry from CAD is not necessary, thus the caliper can be optimized for a variation of its geometrical and physical parameters. With this modeling approach, typical performance criteria such as caliper fluid displacement, hysteresis, uneven pad wear and residual torque can be calculated in a virtual bench test.

Driver assistance features have been introduced to the market focusing on basic, independent functional scenarios. The trend is showing that these kinds of products are facing more and more complex scenarios and we are transitioning from single independent functions to a strongly networked system. Some of the drivers for future autonomous vehicles are 360° monitoring by active safety technology and V2X (vehicle to vehicle or vehicle to infrastructure) communication. In the past vehicles were strictly operated by the driver. Advanced driver assistance products added so called feedback features like lane departure warning, forward collision warning, and blind spot monitoring. First steps towards semi-autonomous driving started with the development of active support functions like adaptive cruise control or lane keeping support. Collision mitigation with various authority levels is the next milestone towards automation followed by other, even more advanced, features.

This paper presents a novel encoding scheme as an alternative to Analog amplitude encoding for communicating sensor signals. The scheme has the potential of becoming a non-proprietary industrial standard for communicating sensor information to electronic control modules. Key features of the encoding scheme are the ability to communicate two sensor values using only 3 wires (power, ground and signal) with 12 bit resolution within 1ms. The scheme includes a checksum for error detection and a mechanism for reporting serial data such as low rate sensor information, part numbers or fault codes. Data is communicated to the receiving module by varying the time between discrete (single edge polarity) transitions. The encoding is self-calibrating and does not require an expensive crystal in the sending module (assumed to be a low-cost ASIC) to maintain signal integrity.

Compressed natural gas (CNG) is an attractive, alternative fuel for spark-ignited (SI), internal combustion (IC) engines due to its high octane rating, and low energy-specific CO2 emissions compared with gasoline. Directly-injected (DI) CNG in SI engines has the potential to dramatically decrease vehicles’ carbon emissions; however, optimization of DI CNG fueling systems requires a thorough understanding of the behavior of CNG jets in an engine environment. This paper therefore presents an experimental and modeling study of DI gaseous jets, using methane as a surrogate for CNG. Experiments are conducted in a non-reacting, constant volume chamber (CVC) using prototype injector hardware at conditions relevant to modern DI engines. The schlieren imaging technique is employed to investigate how the extent of methane jets is impacted by changing thermodynamic conditions in the fuel rail and chamber.

Accuracy of clutch torque model which converts target torque to target stroke is essential to control the dry clutch system. Continuous Adaptation algorithm requires micro slip control during in-gear driving. Clutch judder during micro slip control can cause detrimental effect on the output of controller as slip speed is calculated by deviation of engine speed and clutch speed. Conventional approach to avoid clutch judder is using low pass filter to the input of controller which is slip speed. But this affect to the overall response time of slip controller. In this paper, signal processing algorithm is design and tested for the clutch speed(Input shaft speed). With low pass filter in clutch speed, clutch judder signal is decreased but overall time delay creates static error during acceleration. Several phase advance algorithm is designed to overcome the static error during acceleration without disadvantage of decreasing clutch judder signal.

Global automotive fuel economy and emissions pressures mean that 48 V hybridisation will become a significant presence in the passenger car market. The complexity of powertrain solutions is increasing in order to further improve fuel economy for hybrid vehicles and maintain robust emissions performance. However, this results in complex interactions between technologies which are difficult to identify through traditional development approaches, resulting in sub-optimal solutions for either vehicle attributes or cost. The results presented in this paper are from a simulation programme focussed on the optimisation of various advanced powertrain technologies on 48 V hybrid vehicle platforms. The technologies assessed include an electrically heated catalyst, an insulated turbocharger, an electric water pump and a thermal management module.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Since several decades, passenger cars and light duty vehicles (LDV) with spark-ignited engines reach full pollutant conversion during warm up conditions; the major challenge has been represented by the cold start and warming up strategies. The focus on technology developments of exhaust after treatment systems have been done in the thermal management in order to reach the warm up conditions as soon as possible. A new challenge is now represented by the Real Driving Emission (RDE) Regulation as this bring more various, and not any longer cycle defined, cold start conditions. On the other hand, once the full conversion has been reached, it would be beneficial for many Exhaust After Treatment System (EATS) components, e.g. for overall durability if the exhaust gas temperature could be lowered. To take significant further emission steps, approaching e.g. zero emission concepts, we investigate the use of Electrical Heating Catalyst (EHC) also including pre-heating.

Riveting is a process used to fasten printed circuit board to housing that offers several advantages compared to screws. This involves a cylindrical pin that protrudes from the housing being compressed with a concave tool to produce a rivet head that fills the PCB hole and holds it in place over service life of the component. The process as performed currently in-house uses parameters that have not been optimized. Testing has revealed that the process is subjecting the PCB to surface strains higher than 1000μɛ which is the limit as recommended by standards. Exceeding this limit reduces the reliability of electrical components and increases risk of field failures. This risk can be mitigated by improving the riveting process parameters to prevent high strain from reaching components. Having a finite element model for high deformation problems is an essential prerequisite to explore riveting process improvement.